7 Flashcards
(17 cards)
What is homeostasis?
Homeostasis is the maintenance of stable internal conditions in an organism.
How is homeostasis maintained at the cellular level?
It is maintained by the cell membrane controlling movement of substances in and out of the cell.
What is the function of the cell membrane?
The cell membrane selectively controls what goes in and out of the cell.
What types of molecules cannot pass easily through the cell membrane?
Polar and/or large molecules.
How is cell transport classified?
Cell transport is classified as either passive or active.
What is passive transport?
Passive transport requires no extra energy as molecules move from high to low concentration.
Give examples of passive transport.
- Simple diffusion
- Facilitated diffusion
- Osmosis
What is active transport?
Active transport requires extra energy (ATP) to move materials from low to high concentration.
Give examples of active transport.
- Molecular pumps
- Exocytosis
- Endocytosis
What is a solute?
A solute is what gets dissolved.
What is a solvent?
A solvent is what does the dissolving.
What is a solution?
A solution is a uniform mixture of two or more substances.
What does concentration refer to?
Concentration refers to the amount of solute dissolved in a solvent.
What is the abbreviation symbol for concentration?
[ ]
What is a concentration gradient?
A concentration gradient is the difference in concentration of a substance from one location to another.
Fill in the blank: Passive transport requires _______ energy by the cells.
no
Fill in the blank: Active transport moves materials from _______ to _______ concentration.
low, high
